Infrared Spectroscopy of Astrophysical Gas, Grains, and Ices with Sofia

1. Infrared Spectroscopy of AstrophysicalGas, Grains, and Ices with Sofia R. D. Gehrza and E. E. Becklinb aUniversity of Minnesota bUniversities Space Research Association http://www.sofia.usra.edu 64th International Symposium on Molecular Spectroscopy , Columbus, OH, June 23, 2009

2. Outline • SOFIA and the Chemical Evolution of the Universe • Science addressed by Infrared Spectroscopy with SOFIA • Summary 64th International Symposium on Molecular Spectroscopy , Columbus, OH, June 23, 2009

3. Studying the Chemical Universe with SOFIA Star Death Star Birth 64th International Symposium on Molecular Spectroscopy , Columbus, OH, June 23, 2009

4. Sources Embedded in Massive Cloud Cores Van Dishoech et al., ApJ, 502, L173 (1998) Gezari, Backman, and Werner, ApJ 509, 283 (1998) NASA, C.R. O'Dell and S.K. Wong (Rice University) Pestalozzi et al., A&A, 448, L57 (2006) Whittet et al., A&A, 315, L357 (1996) 2.5 45 64th International Symposium on Molecular Spectroscopy , Columbus, OH, June 23, 2009

5. The chemistry of disks with radius and Age • High spatial and spectral • resolution can determine • where different species • reside in the disk • small radii produce • double-peaked, wider lines. • Observing • many disks • at different • ages will trace • disk chemical • evolution 64th International Symposium on Molecular Spectroscopy , Columbus, OH, June 23, 2009

6. Astrochemistry in Star Forming Regions NGC2024 • SOFIA is the only mission that can provide spectrally resolved data on the 63 and 145 m [OI] lines to shed light on the oxygen deficit in circumstellar disks and star-forming clouds • SOFIA has the unique ability to spectrally resolve water vapor lines in the Mid-IR to probe and quantify the creation of water in disks and star forming environments Kandori, R., et al. 2007, PASJ, 59, 487 64th International Symposium on Molecular Spectroscopy , Columbus, OH, June 23, 2009

7. Thermal Emission from ISM Gas and Dust • SOFIA is the only mission in the next decade that is sensitive to the entire Far-IR SED of a galaxy that is dominated by emission from the ISM excited by radiation from massive stars and supernova shock waves • The SED is dominated by PAH emission, thermal emission from dust grains, and by the main cooling lines of the neutral and ionized ISM NGC2024 Kandori, R., et al. 2007, PASJ, 59, 487 Spectral Energy Distribution (SED) of the entire LMC (courtesy of F. Galliano) 64th International Symposium on Molecular Spectroscopy , Columbus, OH, June 23, 2009

8. SOFIA and Classical Nova Explosions What can SOFIA tell us about gas phase abundances in Classical Nova Explosions? • Gas phase abundances of CNOMgNeAl • Contributions to ISM clouds and the primitive Solar System • Kinematics of the Ejection 64th International Symposium on Molecular Spectroscopy , Columbus, OH, June 23, 2009

9. SOFIA Observations of ISM HD • The 112m ground-state rotational line of HD is accessible to GREAT • ISO detection of SGR B shows that HD column densities • of ~ 1017 – 1018 cm-2can be detected • All deuterium in the Universe was • originally created in the Big Bang • D is destroyed by astration in stars • Therefore, D abundance probes the ISM • that has never been cycled through stars • 112 m observations of HD can be used to determine ISM H/D abundances • Cold HD (T<50K) is a proxy for cold molecular Hydrogen, • The 112 m line can be used to map the Galactic distribution of cold • molecular gas just as 21 cm maps the distribution of neutral hydrogen Atmospheric transmission around the HD line at 40,000 feet 64th International Symposium on Molecular Spectroscopy , Columbus, OH, June 23, 2009

10. Observing Comets with SOFIA • Comet nuclei are the Rosetta Stone of the Solar System and • contain a frozen record of the contents and physical conditions of the primitive Solar Nebula • Comet nuclei, comae, tails, and trails emit primarily at the thermal IR wavelengths accessible with SOFIA • IR Emission features from grains, ices, and molecular gases are strongest when comets are near perihelion • SOFIA has unique advantages: IR Space platforms like • Spitzer, Herschel, and JWST cannot view comets during • perihelion passage due to pointing constraints 64th International Symposium on Molecular Spectroscopy , Columbus, OH, June 23, 2009

11. SOFIA and Comets: Mineral Grains What can SOFIA observations of comets tell us about the origin of the Solar System? ISO Data • Comet dust mineralogy: amorphous, crystalline, and organic constituents • Comparisons with IDPs and meteorites • Comparisons with Stardust • Only SOFIA can make these observations near perihelion Spitzer Data The vertical lines mark features of crystalline Mg-rich crystalline olivine (forsterite) 64th International Symposium on Molecular Spectroscopy , Columbus, OH, June 23, 2009

12. SOFIA and Comets: Gas Phase Constituents What can SOFIA observations of comets tell us about the origin of the Solar System? C. E. Woodward et al. 2007, ApJ, 671, 1065 B. P. Bonev et al. 2007, ApJ, 661, L97 Theory C/2003 K4 Spitzer • Production rates of water and other volatiles • Water H2 ortho/para (parallel/antiparallel) hydrogen spin isomer ratio gives the water formation temperature; a similar analysis can done on ortho/para/meta spin isomers of CH4 • Only SOFIA can make these observations near perihelion 64th International Symposium on Molecular Spectroscopy , Columbus, OH, June 23, 2009

13. Summary • SOFIA will be a premier facility for far-IR and submillimeter spectroscopy for many years • It will be especially effective for studies of the physics and chemistry of: • Luminous young stellar objects • Proto-planetary disks • The winds of evolved stellar systems • Regions of star formation and ISM clouds • Comets and planetary atmospheres Our Web site:http://www.sofia.usra.edu/ This talk:http://www.sofia.usra.edu/Science/speakers/index.html 64th International Symposium on Molecular Spectroscopy , Columbus, OH, June 23, 2009

14. Backup 64th International Symposium on Molecular Spectroscopy , Columbus, OH, June 23, 2009

15. SOFIA Will Study the Diversity of Stardust Herbig AeBe Post-AGB and PNe Mixed chemistry post-AGB C-rich AGB O-rich AGB Mixed chemistry AGB Deeply embedded YSO HII region refection nebulae • ISO SWS Spectra: stardust is spectrally diverse in the regime covered by SOFIA • Studies of stardust mineralogy • Evaluation of stardust contributions from various stellar populations • Implications for the lifecycle of gas and dust in galaxies Kandori, R., et al. 2007, PASJ, 59, 487 64th International Symposium on Molecular Spectroscopy , Columbus, OH, June 23, 2009

16. Thermal Emission from PAH Rich Objects • A key question is whether portions of the aromatic population of PAHs are converted to species of biological significance • Far-IR spectroscopy can constrain the size and shape of PAH molecules and clusters. • The lowest lying vibrational modes (“drumhead” modes) will be observed by SOFIA’s spectrometers NGC2024 Kandori, R., et al. 2007, PASJ, 59, 487 Vibrational modes of PAHs in a planetary nebula and the ISM (A. Tielens 2008) 64th International Symposium on Molecular Spectroscopy , Columbus, OH, June 23, 2009

17. Transits provide good estimates for the mass, size and density of the planet Transits may reveal the presence of, satellites, and/or planetary rings SOFIA and Extra-solar Planet Transits How will SOFIA help us learn about the properties of extra-solar planets? • More than 268 extra-solar planets; more than 21 transit their primary star • SOFIA flies above the scintillating component of the atmosphere where it • can detect transits of planets across bright stars at high signal to noise a) HD 209458b transit: a) artist’s concept and b) HST STIS data b) 64th International Symposium on Molecular Spectroscopy , Columbus, OH, June 23, 2009